New Silicon Chip-Based Quantum Computer Passes Major Test

New Silicon Chip-Based Quantum Computer Passes Major Test
Published on February 14, 2018 at 11:58PM
An anonymous reader quotes a report from Gizmodo: Researchers from two teams now working with Intel have reported advances in a new quantum computing architecture, called spin qubits, in a pair of papers out today. They’re obviously not the full-purpose quantum computers of the future. But they’ve got a major selling point over other quantum computing designs. “We made these qubits in silicon chips, similar to what’s used in classical computer processes,” study author Thomas Watson from TU Delft in the Netherlands told me. “The hope is that by doing things this way, we can potentially scale up to larger numbers needed to perform useful quantum computing.”

Today, a research group at TU Delft, called QuTech, announced that they’d successfully tested two “spin qubits.” These qubits involve the interaction of two confined electrons in a silicon chip. Each electron has a property called spin, which sort of turns it into a tiny magnet, with two states: “up” and “down.” The researchers control the electrons with actual cobalt magnets and microwave pulses. They measure the electron’s spins by watching how nearby electric charges react to the trapped electrons’ movements. Those researchers, now working in partnership with Intel, were able to perform some quantum algorithms, including the well-known Grover search algorithm (basically, they could search through a list of four things), according to their paper published today in Nature. Additionally, a team of physicists led by Jason Petta at Princeton reported in Nature that they were able to pair light particles, called photons, to corresponding electron spins. This just means that distant spin qubits might be able to talk to one another using photons, allowing for larger quantum computers. There are some advantages to these systems. “Present-day semiconductor technology could create these spin qubits, and they would be smaller than the superconducting chips used by IBM,” reports Gizmodo. “Additionally, they stay quantum longer than other systems.” The drawbacks include the fact that it’s very difficult to measure the spins of these qubits, and even more difficult to get them to interact with each other. UC Berkeley postdoc Sydney Schreppler also mentioned that the qubbits needed to be really close to each other.